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-rw-r--r--examples/simple_ising.cpp192
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diff --git a/examples/simple_ising.cpp b/examples/simple_ising.cpp
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index 24e4ae5..0000000
--- a/examples/simple_ising.cpp
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@@ -1,192 +0,0 @@
-
-#include <getopt.h>
-#include <iostream>
-
-#include "include/randutils/randutils.hpp"
-
-#include <wolff.hpp>
-
-// define your R_t and X_t. here both are the same, ising_t
-class ising_t {
- public:
- bool x;
-
- // both X_t and R_t need a default constructor (and destructor, if relevant)
- ising_t() : x(false) {}
- ising_t(bool x) : x(x) {}
-
- // R_t needs the member functions
- // X_t act(const X_t& s) const {}
- // R_t act(const R_t& s) const {}
- // to define action on both spins and other transformations
- ising_t act(const ising_t& s) const {
- if (x) {
- return ising_t(!(s.x));
- } else {
- return ising_t(s.x);
- }
- }
-
- // R_t needs the member functions
- // X_t act_inverse(const X_t& s) const {}
- // R_t act_inverse(const R_t& s) const {}
- // to define action of its inverse on both spins and other transformations
- ising_t act_inverse(const ising_t& s) const {
- return this->act(s);
- }
-};
-
-// define how measurements should be taken by importing the interface wolff_measurement<R_t, X_t>
-class ising_measurements : public wolff_measurement<ising_t, ising_t> {
- private:
- count_t n;
-
- double E;
- int M;
- v_t S;
-
- double totalE;
- double totalM;
- double totalS;
-
- public:
- ising_measurements(D_t D, L_t L, double H) {
- n = 0;
- M = (int)pow(L, D);
- E = -D * pow(L, D) - H * pow(L, D);
-
- totalE = 0;
- totalM = 0;
- totalS = 0;
- }
-
- void pre_cluster(const state_t<ising_t, ising_t>& s, count_t step, count_t N, v_t v0, const ising_t& R) {
- S = 0;
- }
-
- void plain_bond_added(v_t v, const ising_t& s_old, const ising_t& s_new, v_t vn, const ising_t& sn, double dE) {
- E += dE;
- }
-
- void ghost_bond_added(v_t v, const ising_t& s_old, const ising_t& s_new, double dE) {
- E += dE;
-
- if (s_old.x) {
- M++;
- } else {
- M--;
- }
-
- if (s_new.x) {
- M--;
- } else {
- M++;
- }
- }
-
- void plain_site_transformed(v_t v, const ising_t& s_old, const ising_t& s_new) {
- S++;
- }
-
- void ghost_site_transformed(const ising_t& R_old, const ising_t& R_new) {
- }
-
- void post_cluster(const state_t<ising_t, ising_t>& s, count_t step, count_t N) {
- totalE += E;
- totalM += M;
- totalS += S;
- n++;
- }
-
- double avgE() {
- return totalE / n;
- }
-
- double avgM() {
- return totalM / n;
- }
-
- double avgS() {
- return totalS / n;
- }
-};
-
-int main(int argc, char *argv[]) {
-
- // set defaults
- count_t N = (count_t)1e4;
- D_t D = 2;
- L_t L = 128;
- double T = 2.26918531421;
- double H = 0.0;
-
- int opt;
-
- // take command line arguments
- while ((opt = getopt(argc, argv, "N:D:L:T:H:")) != -1) {
- switch (opt) {
- case 'N': // number of steps
- N = (count_t)atof(optarg);
- break;
- case 'D': // dimension
- D = atoi(optarg);
- break;
- case 'L': // linear size
- L = atoi(optarg);
- break;
- case 'T': // temperature
- T = atof(optarg);
- break;
- case 'H': // external field
- H = atof(optarg);
- break;
- default:
- exit(EXIT_FAILURE);
- }
- }
-
- // define the spin-spin coupling
- std::function <double(const ising_t&, const ising_t&)> Z = [] (const ising_t& s1, const ising_t& s2) -> double {
- if (s1.x == s2.x) {
- return 1.0;
- } else {
- return -1.0;
- }
- };
-
- // define the spin-field coupling
- std::function <double(const ising_t&)> B = [=] (const ising_t& s) -> double {
- if (s.x) {
- return -H;
- } else {
- return H;
- }
- };
-
- // initialize the system
- state_t<ising_t, ising_t> s(D, L, T, Z, B);
-
- // initialize the random number generator
- randutils::auto_seed_128 seeds;
- std::mt19937 rng{seeds};
-
- // define function that generates self-inverse rotations
- std::function <ising_t(std::mt19937&, const ising_t&)> gen_R = [] (std::mt19937&, const ising_t& s) -> ising_t {
- return ising_t(true);
- };
-
- // initailze the measurement object
- ising_measurements m(D, L, H);
-
- // run wolff N times
- wolff<ising_t, ising_t>(N, s, gen_R, m, rng);
-
- // print the result of our measurements
- std::cout << "Wolff complete!\nThe average energy per site was " << m.avgE() / s.nv
- << ".\nThe average magnetization per site was " << m.avgM() / s.nv
- << ".\nThe average cluster size per site was " << m.avgS() / s.nv << ".\n";
-
- // exit
- return 0;
-}
-